1. Field of the Invention
The present invention relates to a collision sensing apparatus, and more particularly to a collision sensing apparatus for detecting a side collision of a vehicle.
2. Description of the Related Art
Conventionally, collision sensing apparatuses are known which detect a collision from a lateral direction of a vehicle at the time of a collision of the vehicle and actuate an air bag apparatus to deploy an air bag between an inner side portion of the vehicle and a side portion of the vehicle. One example of such collision sensing apparatuses is disclosed in Japanese Patent Application Laid-Open (JP-A) No. 6-64491.
Further, in relation to collision sensing apparatuses, a method and apparatus for supplying inflating signals for inflating an air bag device are disclosed in Japanese Patent Application Laid-Open (JP-A) No. 8-67227, and actuating apparatuses for air bag devices are disclosed in International Application Publication No. wo95/31357 and German Patent No. DE4309827A1.
As shown in FIG. 11, inside a seat 70, this collision sensing apparatus is provided with an air bag apparatus 72 and a sensor 76 for actuating the air bag apparatus 72 to inflate an air bag body 74 accommodated in the air bag apparatus 72. This sensor 76 is disposed at an end of a frame 78 of a seat cushion 70A of the seat 70.
With this collision sensing apparatus, however, since collision over a wide range are detected by a single sensor, the sensor 76 is arranged to be operated by a collision load at the time of a side collision which is transmitted by means of a plastic block provided in the door and a frame member provided in the seat 70. For this reason, the weight and cost of the apparatus increase substantially.